HR: 17:24h
AN: A44A-08    [Abstracts]
TI: Analysis of the Structure and Evolution of the Madden-Julian Oscillation Using AIRS Data
AU: Tian, B
EM: btian@gps.caltech.edu
AF: California Institute of Technology, Division of Geological and Planetary Sciences, MC 170-25 1200 E. California Blvd., Pasadena, CA 91125 United States
AU: * Waliser, D D
EM: duane.waliser@jpl.nasa.gov
AF: Jet Propulsion Laboratory, 4800 Oak Grove Drive, MS 183-505, Pasadena, CA 91109 United States
AU: Fetzer, E
EM: Eric.J.Fetzer@jpl.nasa.gov
AF: Jet Propulsion Laboratory, 4800 Oak Grove Drive, MS 183-505, Pasadena, CA 91109 United States
AU: Lambrightsen, B
EM: Bjorn.H.Lambrigtsen@jpl.nasa.gov
AF: Jet Propulsion Laboratory, 4800 Oak Grove Drive, MS 183-505, Pasadena, CA 91109 United States
AU: Yung, Y
EM: yly@gps.caltech.edu
AF: California Institute of Technology, Division of Geological and Planetary Sciences, MC 170-25 1200 E. California Blvd., Pasadena, CA 91125 United States
AB: Since its discovery, the Madden and Julian Oscillation [MJO; a.k.a. Intraseasonal Oscillation (ISO)] has continued to be a topic of significant interest due to its complex nature and the wide range of phenomena it interacts with. For example, the onset and break activity of the Asian-Australian monsoon system are strongly influenced by the propagation and evolution of MJO events. Apart from this significant local influence, there are also important downstream influences that arise from the MJO. This includes the development of persistent North Pacific circulation anomalies, including extreme rainfall events along the western United States, during Northern Hemisphere winter that have been linked to the evolution and eastward progression of convective anomalies associated with MJO events. In addition, MJO convective activity has been linked to Northern Hemisphere summer time precipitation variability over Mexico and South America as well as to wintertime circulation anomalies over the Pacific - South American Sector. Studies have also shown that particular phases of the MJO are more favorable than others in regards to the development of tropical storms/hurricanes in both the Atlantic and Pacific sectors. Finally, the passage of MJO events over the western Pacific Ocean has been found to significantly modify the thermocline structure in the equatorial eastern Pacific Ocean via their connection to westerly wind bursts. This latter interaction has even been suggested to play an important role in triggering variations in El Nino - Southern Oscillation (ENSO). As influential as the MJO is on our weather and climate, we still struggle to properly represent the MJO in our general circulation models (GCMs) used for weather prediction and climate simulation. The greatest uncertainty in this representation is associated with the hydrological components, namely water vapor, cloud and the condesation/evaporation processes. Most work to date on diagnosing this problem and trying to improve model representations of the convective and other cloud processes has been restricted to analysis of 2-dimensional data in the horizontal plane (e.g., OLR, upper-level winds, surface characteristics). In this study, we seek to exploit the three-dimensional spatial structure afforded by AIRS data along with its high spatial and temporal resolution to better understand the spatial-temporal evolution of the MJO, particularly in regards to moist processes. Our goal is to develop an observed depiction of the MJO evolution from AIRS and supporting data sets (e.g., TRMM) and compare this to GCMs to learn what aspects of the physics may not be properly represented in the models.
DE: 1655 Water cycles (1836)
DE: 1620 Climate dynamics (3309)
DE: 1640 Remote sensing
DE: 0325 Evolution of the atmosphere
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting